A deranged man shouting racial remarks and – crying “this is American blood!” – smeared blood across the shirt of a Bangladeshi-American store clerk yesterday in what police were calling a possible bias crime.

Christopher Sackmann, 31, of Queens, allegedly attacked Zohir Zahan, 30, hitting him in the face, shouting obscenities directed at Muslims and covering him in blood – after he cut his hand by punching a store refrigerator at the Malik Grocery in Sunnyside, cops said.

“He started smacking my counter,” Zahan said. “He smacked my refrigerator and banged his head on the counter.